I concur in the majority’s disposition of Sims’s guilt-phase claims, but I must respectfully dissent from the denial of habe-as relief with respect to Sims’s death sentence, and in particular from Parts III-B, VI, and IX of the majority opinion.
I view this case through a different lens than does the majority. I conclude that constitutional error infected Sims’s trial in two respects that I will elaborate. I then turn to Brecht v. Abrahamson, 507 U.S. 619, 113 S.Ct. 1710, 123 L.Ed.2d 353 (1993), to determine whether the constitutional errors had “substantial and injurious effect or influence in determining the jury’s verdict.” Id. at 623, 113 S.Ct. 1710 (citation and internal quotation marks omitted). I add the gloss of O’Neal v. McAninch, 513 U.S. 432, 115 S.Ct. 992, 130 L.Ed.2d 947 (1995), which instructs that if there is “grave doubt” as to the effect of the constitutional errors, the petitioner is entitled to relief. Id. at 436, 115 S.Ct. 992.
In this death penalty case, I take this “grave doubt” standard very seriously and have viewed this case in that light. I conclude that the determination of guilt must stand despite constitutional error. In my view, it did not have a substantial and injurious effect or influence in determining the jury’s verdict. .There was too much compelling evidence of guilt. However, the constitutional error carried over into the penalty phase, and together with additional error introduced into the penalty phase, engénders “grave doubt” as to what effect or influence the constitutional errors had on the jury’s verdict.
The penalty phase was marred by two constitutional errors: the prosecutor’s use of Sims’s inculpatory statements obtained in violation of Miranda, and the prosecutor’s insistence that the compelling evidence of Sims’s childhood abuse could not be considéred by the jury in mitigation. Because there is “grave doubt” as to the effect of these errors, the district court’s denial of the writ with respect to Sims’ death sentence should be reversed.
I. Miranda Error
The majority ignores the fact that the California Supreme Court held that the admission of crucial portions of Officer Perkins’s interrogation of Sims violated Miranda v. Arizona, 384 U.S. 436, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966). People v. Sims, 5 Cal.4th 405, 20 Cal.Rptr.2d 537, *590858 P.2d 992, 1015 (Cal.1993).1 I agree with the California Supreme Court that the admission of Sims’s inculpatory statements was error. I conclude further that the manner in which the statements were used by the prosecution had a substantial and injurious effect on the jury’s penalty phase deliberations.2
Once having invoked his right to silence and to have an attorney present during questioning, a suspect “is not subject to further interrogation by the authorities until counsel has been made available, unless the accused himself initiates further communication.” Edwards v. Arizona, 451 U.S. 477, 484-85, 101 S.Ct. 1880, 68 L.Ed.2d 378 (1981). A suspect initiates further communication of his own accord only when he “evinee[s] a willingness and a desire for a generalized discussion about the investigation.” Oregon v. Bradshaw, 462 U.S. 1039, 1045-46, 103 S.Ct. 2830, 77 L.Ed.2d 405 (1983). If police then begin anew with interrogation of the suspect, the prosecution must demonstrate under the totality of the circumstances that the suspect has knowingly and intelligently waived his previously invoked rights. Edwards, 451 U.S. at 486 n. 9, 101 S.Ct. 1880. “Interrogation” in this context may be express questioning or “any words or actions on the part of the police (other than those normally attendant to arrest and custody) that the police should know are reasonably likely to elicit an incriminating response.” Rhode Island v. Innis, 446 U.S. 291, 301, 100 S.Ct. 1682, 64 L.Ed.2d 297 (1980).
On December 25, Sims unequivocally invoked his rights to silence and to have an attorney present during questioning. Once this occurred, Perkins prepared to leave the interrogation room. Perkins’s own testimony then establishes 1) that Sims asked questions narrowly directed at issues relating to extradition, 2) that Perkins responded with a rambling explanation of his role in the investigation and details from the crime scene, and 3) that only after Perkins had related this extensive crime-scene information did Sims state “I had to kill that boy.”
The California Supreme Court’s determination that Perkins’s response was “nonresponsive to [Sims’s] inquiry and *591served no legitimate purpose incident to [Sims’s] arrest or custody” was entirely correct. Sims?s statement cannot be read to “evince[ ] a willingness and a desire for a generalized discussion about the investigation.” Bradshaw, 462 U.S. at 1045-46, 103 S.Ct. 2830. Rather, Sims was asking simple questions about extradition.3 Perkins’s responses, in contrast, went directly to the substance of the investigation; at one point Perkins even stated that he had “reason to believe that [Sims] and a female companion occupied that room prior to the demise of Mr. Harrigan.” This statement was reasonably likely to elicit a response from Sims related to whether or not he had occupied the room, and whether or not he killed Harrigan. Thus, Perkins’s non-responsive narrative was tantamount to further interrogation and in violation of Miranda and its progeny.
Following this straightforward confession, Perkins continued to ply Sims with details of the murder, even remarking that Harrigan did not need to die in that manner. Both the Supreme Court of California and the district court concluded that Perkins’s statements were likely to elicit an incriminating response, and Sims’s response that “he would have identified me” should have been suppressed. This conclusion is correct for the reasons stated in those opinions.
The following day, Sims requested to see the Glendale officers once more. When he mentioned that people thought he was crazy and might kill himself, Perkins asked him if he would, and stated that he didn’t “seem like that kind of guy.” Sims remarked that he was not suicidal, and that he was “not a murderer either.” Perkins’s statements until that point cannot be characterized as interrogation, as they were not “reasonably likely to elicit an incriminating response.” I have no quarrel with the admission of this statement.
However, when Perkins then asked Sims “What does that mean?” Perkins was posing a question that was likely to elicit an incriminating response. This is exactly what happened, as Sims confessed, “That means that I just got drunk, and I didn’t know what the fuck I was — I knew I was doing it, but I shouldn’t [have] done it.” The district court concluded that this statement should have been suppressed. I agree.
In all, I conclude that three of the four incriminating statements were admitted into evidence by the trial court in violation of Miranda and its progeny.
II. The Miranda Error’s Injurious Effect
The majority concludes that whatever Fifth Amendment error occurred was harmless with respect to both phases of Sims’s trial. Though I cannot say that the admission of Sims’s confessions to Officer Perkins had a “substantial and injurious effect or influence in determining the jury’s verdict,” Brecht, 507 U.S. at 623, 113 S.Ct. 1710 (citation and internal quotation marks omitted), at the guilt phase of Sims’s trial, it did have such an effect on the penalty phase deliberations.
Throughout both phases of the trial, the jury heard numerous and extensive references to the December 25 and 26 incriminating statements, both during the *592presentation of the evidence and the prosecution’s argument. During the guilt phase, Officer Montecuollo testified that Sims had confessed that “I had to Mil that boy” during the December 25 interview. The jury heard the same statement twice more during Montecuollo’s cross examination, and twice more on re-direct. Officer PerMns corroborated that testimony, stating that when he described the investigation and the crime scene, Sims twice said, “I had to Mil that boy,” then that “he was going to identify me.” The statement “I had to Mil that boy” was then repeated once more during direct testimony, four more times on cross examination, and two more times on re-direct.4 Officer PerMns went on to testify-as to the December 26 interview, recounting Sims’s admission that, “That means that I just got drunk. I didn’t know what the fuck I was-I knew what I was doing but shouldn’t have done it.” This same statement was heard again by the jury when the prosecution played the cassette tape of the December 26 conversation between Perkins and Sims. A copy of the transcript of that taped conversation was admitted into evidence over defense counsel’s objection, read in part to the jury during the prosecution’s closing, and allowed into the jury room during deliberations.
The use of these incriminating admissions was central to the prosecutor’s closing argument in the guilt phase. After using the statement “I had to Mil that boy” four more times during the closing to show intent to kill, the prosecutor used the phrase as a refrain in his rebuttal. In bolstering Officer Montecuollo’s credibility, the prosecutor stressed three times how important the statement was. The prosecutor explained that Montecuollo’s failure to remember Sims’s explanation that Har-rigan could have identified him was not significant because “[Montecuollo and Perkins] both remember the key important part: I had to kill that boy. That’s the important part of that conversation” (emphasis added). The prosecutor then continued:
It is only natural that things — that people’s memories begin to fade, accept [sic] for the really important things, and the important thing was: I had to kill that boy.
But here is a man that is coming into court and telling you the honest truth. That’s what he recalls. And it is important because of what he recalls. He recalls the important part of that conversation, which is: I had to kill that boy.
(emphasis added). The prosecutor then spent a comparable amount of time expounding on the importance of Sims’s other admission: “I knew I was doing it, but I shouldn’t [have] done it.” Repeating the statement several times, the prosecutor argued that it conclusively confirmed Sims’s intent to Mil.
During the penalty phase, the prosecution again played the tape of Sims’s admission that “I just got drunk, and I didn’t know what the fuck I was, I knew I was doing it, but I shouldn’t [have] done it.” Then, in his penalty phase closing argument, the prosecutor reiterated once again for the jury Sims’s two most damning statements: “I had to Mil that boy” and “I knew I was doing it but I shouldn’t [have] done it.” Specifically, the prosecutor used “I had to Mil that boy” in conjunction with a hypothesis about how the murder might have taken place:
*593We can assume that John Harrigan would want to live. Raises his head out of the water and it would take Mitchell Sims to push his head back under the water. What did Mitchell Sims say?. “I had to kill that boy.” And that’s how he killed John Harrigan.
In sum, the improperly admitted statements were repeated throughout the proceedings, becoming a refrain for the prosecution.
The prosecution’s use of these statements prejudiced Sims’s capital sentencing proceeding in two ways.. First, the use of Sims’s statements reflecting his intent to kill Harrigan completely foreclosed any residual doubt argument Sims might have mounted with respect to his intent to kill. We have recently reiterated that reliance on residual doubt is an acceptable penalty phase strategy. See Williams v. Woodford, 384 F.3d 567, 617-17 (9th Cir.2004). Here, the evidence of intent was strong enough that, after considerable review and study of the record, I cannot say Sims’s statements to Perkins had a “substantial and injurious effect or influence” on the jury’s determination of Sims’s intent beyond a reasonable doubt, and therefore I agree with the majority that Sims was not prejudiced at the guilt-phase. However, there were lingering questions about Sims’s intent to kill that, absent the introduction of Sims’s admission “I had to kill that boy,” could have prevented the jury at the penalty phase from finding Sims’s intent beyond all possible doubt (the standard for lingering doubt). During the guilt phase, defense counsel argued that evidence such as the cut phone cord, Sims’s deliberate misstatement to Sicam and Spiroff that he and Padgett were headed to San Francisco, the slackness of the ligature around Harrigan’s neck, and the fact that the bathtub drain was unplugged, raised a doubt as to Sims’s intent to kill. Sims’s admissions blunted any potential impact this evidence may have had in support of a residual doubt theory. Unsurprisingly, the defense’s argument that Sims lacked intent was entirely abandoned during the penalty phase, and defense counsel did not press a residual doubt argument- with any specificity or vigor. Meanwhile the prosecutor was able to argue .very effectively during the penalty phase that the case had been proved beyond all possible doubt. Had Sims’s crucial statements to Officer Perkins — “I had to kill that boy” and “I knew I .was doing it” — been excluded (as they should have been), the prosecutor’s argument on this score would have been open to challenge and the residual doubt question would have been very much in play, as several of Sims actions appear inconsistent with an intent to kill. The effect of admitting the statements, then, was to eliminate an entire legitimate and effective argument in favor of sparing Sims’s life.
Second, the prosecutor used Sims’s statements as the foundation of his extensive argument that Sims lacked remorse. The prosecutor argued:
... [N]o remorse. Now, many things go into a case in judging what the appropriate punishment should be and we have a statement to Mr. Perkins on the 25th ... [and] on the 26th ....
And I was waiting for those pieces of evidence to hear that Mitchell Sims was sorry. I was waiting to hear that Mitchell Sims felt bad about the years he had stolen. I was waiting for , Mitchell Sims to express remorse, to apologize to somebody for what he had done and what he had taken.
What I heard was a preoccupation with getting cigarettes, seeing his girlfriend Ruby Padgett. I did not hear any of that remorse.- Anything that would tell me that Mitchell Sims will be *594living the rest of his life with his stomach in a knot. That he will be preoccupied with the evil he has done. There is nothing like that.
What did we hear on the 25th? Mitchell Sims looking out for number one. “What is going to happen to me in terms of extradition. I want to see Ruby. I want to go the same place Ruby goes.”
... And then he said, “I had to kill that boy.” And Mr. Perkins indicated, went through the facts of the Glendale case. “Well, you know this kid was tied up and bound and gagged.” Jon Perkins says, “Mitch he didn’t have to die. ” At that point, Mitchell Sims says, ‘Well, I didn’t want him to identify me. ”
Next day Mitchell Sims calls back Jon Perkins and conversation picks up again about cigarettes. He has killed 3 people, tried to kill 2 more, and the first thing on his mind is cigarettes; the second one is Ruby.
And he says, Well, I knew I was doing it, ” and then kicks in as an afterthought, “maybe I shouldn’t have done it.” That’s the only thing, the closest thing we have to even remotely showing remorse for what he did.
(emphasis added).
Sims’s lack of remorse was thus the subject of extended discussion by the prosecutor, and Sims’s December 25 and 26 statements to Officer Perkins were at the heart of the prosecutor’s portrayal of Sims as selfish, unfeeling, and utterly without conscience. The record reflects that the prosecutor repeatedly used the conversations between Sims and Officer Perkins to portray Sims as remorseless. The prosecutor began by drawing the jury’s attention to the most damning of Sims’s statements taken in violation of Miranda: “I had to kill that boy” and “Well, I knew I was doing it ... maybe I shouldn’t have done it.” The prosecutor told the jury that, as he listened to the Perkins interviews, he “was waiting for those pieces of evidence to hear that Mitchell Sims was sorry”; he “was waiting to hear that Mitchell Sims felt bad about the years he had stolen”; he “was waiting for Mitchell Sims to express remorse, to apologize to somebody for what he had done and what he had taken.” What the prosecutor heard instead “was a preoccupation with getting cigarettes, seeing his girlfriend Ruby Padgett”; the prosecutor “did not hear any of that remorse.” The question “where is the remorse?” appears three times in the prosecutor’s argument, along with two other similar formulations: “Where is the knot in his stomach?” and “Where is asking for forgiveness there?” With these questions, the prosecutor drew out the contrast between the type of remorse he would have expected to hear from a person who “ha[s] a conscience,” and the Sims’s passionless confessions— particularly, ‘Well, I knew I was doing it ... maybe I shouldn’t have done it,” a statement the prosecutor characterized as “the only thing, the closest thing we have to even remotely showing remorse for what he did.” The prosecutor’s extensive remarks on the subject of remorse, a point of emphasis in his argument that Sims should be put to death, thus arose directly from the prosecutor’s discussion of Sims’s constitutionally inadmissible statements to Officer Perkins. Sims’s confessions were the force behind the no-remorse argument.
“As the Supreme Court has observed: ‘A confession is like no other evidence. Indeed, the defendant’s own confession is probably the most probative and damaging evidence that can be admitted against him.’ ” Hayes v. Brown, 399 F.3d 972, 986 (9th Cir.2005) (en banc) (quoting Arizona v. Fulminante, 499 U.S. 279, 296, 111 S.Ct. 1246, 113 L.Ed.2d 302 (1991)) (further cita*595tion and internal quotation marks omitted). So it was here. By presenting and emphasizing to the jury Sims’s own admission of intent, the prosecution, foreclosed any residual doubt argument Sims might have made, and Sims’s December 25 and 26 statements became the centerpiece of the argument — featured prominently throughout the prosecutor’s closing — that Sims lacked remorse for his crime.
In spite of the ghastly nature of the crime, a death sentence was not a foregone conclusion in this case. Sims’s decade of tragic abuse at the hands of his stepfather was, even in the prosecutor’s characterization, “shocking.”5 Additionally, had the prosecutor not been able to invoke Sims’s statements taken in violation of Miranda, the jury might have retained lingering doubt as to Sims’s intent and would not have been presented with the prosecutor’s extensive argument that Sims lacked any remorse for his crime. In light of the evidence Sims presented in mitigation and the twin advantages the prosecution gained by its use of Sims’s December 25 and 26 statements, I must conclude that, with respect to the penalty phase, the Miranda violations had a “substantial and injurious effect or influence in determining the jury’s verdict.” Brecht, 507 U.S. at 623, 113 S.Ct. 1710 (citation and internal quotation marks omitted). I would And Sims entitled to relief from his sentence of death on this error alone.
III. Mitigating Evidence: The Prosecutor Misleads the Jury
I also strongly disagree with the majority’s rejection (in Part VI of the opinion) of Sims’s Eighth Amendment claim that the prosecutor repeatedly misstated the law as to the jury’s use of mitigating evidence. The prosecutor misstated the law to the jury in two respects: first, by telling the jury that evidence of a childhood characterized by abuse is simply not a mitigating factor at all because it would apply to practically all criminals; and second, by advising the jury that evidence of Sims’s background does not qualify as mitigating evidence because there is no connection or “bridge” between that background and Sims’s crime. The prosecutor’s use of these misstatements was pervasive during his closing. .As I shall explain, I cannot agree with the majority’s conclusion that these misstatements were merely arguments that' the jury should not attach weight to Sims’s mitigating evidence:' the prosecutor’s misstatements of the law created the overwhelming impression that the jury could not consider evidence of Sims’s dreadful childhood, which was the heart of the evidence he offered to convince the jury to spare his life.6 As a result, the *596capital sentencing proceeding did not comport with the standards of Lockett v. Ohio, 438 U.S. 586, 98 S.Ct. 2954, 57 L.Ed.2d 973 (1978), and its progeny, which require that the capital sentencer consider all relevant mitigating evidence.
In his penalty phase closing, the prosecutor argued:
Now, let’s talk about Mitchell Sims because there was evidence put on about his background. Evidence — certainly is shocking about the evidence.... It certainly paints a very ugly picture.... The question is: what does it mean?
We have had a psychiatrist come in and testify to tell us what it meant.... I have a notation: no bridge. There is nothing to bridge the background of what happened in that family to the murders that we have dealt with here. Nothing to connect it.
And I kept waiting for something to connect it up. Connect it up. What does it mean that person has had an abused childhood? What does it mean in terms of this case right here? There is nothing to connect it up because when Dr. Vicary testified, he said that if you go up to state prison and you talk to violent criminals, murderers, and rapists, and whatever, you find a violent childhood. If you go up to prison and find and talk to murderers and rapists and robbers, you are not going to find a lot of Harvard M.B.A.’s. You are going to find people who in turn were abused as children. What does that mean in terms of mitigation? If, in fact, it were a mitigating factor that a person had a bad childhood, that would apply to vertually [sic] every violent felon currently incarcerated.
If that were, therefore, a mitigating factor, then you would be emptying prisons because it would apply to vertually [sic] everybody.... Were it a mitigating favor that a person had a bad childhood, then you would have no death penalty statute at all.
(emphasis added). After defense counsel objected to this line of argument and was overruled, the prosecutor continued:
So, the question is: what does it mean? Let’s put it in context. Because we are dealing with a common background to a criminal population.... Now, I kept waiting for a bridge. Something to connect this to the offenses here. Some kind of reason why it should be a mitigating factor....
So, again, we are searching for a bridge, we are searching for some kind of bridge. I suppose if the offense was against his stepfather, certainly it would be relevant, then, wouldn’t it? No question about that.
If the offenses here were sexual in nature, for example, rape murders, child molestation murders, then there would be a nexus, you would have that connection there, wouldn’t you? But there aren’t. I mean, there is no bridge. There is no bridge that bridges this bad background to anything we have in the case before us. We have murders of people who were strangers. People who *597were friends. People who were delivering pizzas. There is no connection. Also, we have a gap in time. What happened to Mr. Sims, as bad as it was, was ten years before the crimes in question. A lot of water under the bridge in ten years. The more you analyze it, and I know it sounded terrible when we heard it, we can’t help but be affected by it, but it is the jury’s job to avoid— dispassionately analyze it. What does it mean in terms of assigning a mitigating factor to it? What does it mean in terms of punishment? It doesn’t mean a thing. There is no mitigating factor there.
(emphasis added).
The Supreme Court has repeatedly held that, in a capital sentencing proceeding, “a sentencer may not be precluded from considering, and may not refuse to consider, any relevant mitigating evidence offered by the defendant as the basis for a sentence less than death.” Penry v. Lynaugh, 492 U.S. 302, 318, 109 S.Ct. 2934, 106 L.Ed.2d 256 (1989), overruled on other grounds, Atkins v. Virginia, 536 U.S. 304, 122 S.Ct. 2242, 153 L.Ed.2d 335 (2002); see also Skipper v. South Carolina, 476 U.S. 1, 106 S.Ct. 1669, 90 L.Ed.2d 1 (1986); Eddings v. Oklahoma, 455 U.S. 104, 102 S.Ct. 869, 71 L.Ed.2d 1 (1982); Lockett v. Ohio, 438 U.S. 586, 98 S.Ct. 2954, 57 L.Ed.2d 973 (1978). The sentencer must be able not only to consider but also to “give effect to all relevant mitigating - evidence offered” by a capital defendant. Boyde v. California, 494 U.S. 370, 377-78, 110 S.Ct. 1190, 108 L.Ed.2d 316 (1990) (emphasis added). The Supreme Court has refused to tolerate “[a]ny barrier” to the proper use of mitigating evidence: “Whatever the cause, the conclusion would necessarily be the same: Because the sentencer’s failure to consider all of the mitigating evidence risks erroneous imposition of the death sentence, in plain violation of Lockett, it is our duty to, remand ... for resentencing.” McKoy v. North Carolina, 494 U.S. 433, 442, 110 S.Ct. 1227, 108 L.Ed.2d 369 (1990) (citations, internal quotation marks, and source’s alteration marks omitted).
Regarding the definition of relevant mitigating evidence, the Supreme Court has recently reaffirmed the breadth of the range of evidence that the capital sentencer must be instructed to consider:
“Relevant mitigating evidence is evidence which tends-logically to prove or disprove some fact or circumstance which a fact-finder could reasonably deem to have mitigating value.” Thus, a State cannot bar “the consideration of evidence if the sentencer could reasonably find that it warrants a sentence less than death.”
Tennard v. Dretke, 542 U.S. 274, 124 S.Ct. 2562, 2570, 159 L.Ed.2d 384 (2004) (quoting McKoy, 494 U.S. at 440, 441, 110 S.Ct. 1227) (further citations, internal quotation marks, and source’s alteration marks omitted). Applying this “low threshold for relevance,” id., the Supreme Court specifically rejected the view, espoused by the Fifth Circuit, that mitigating evidence is only relevant if it demonstrates that the defendant had “a uniquely severe permanent handicap” and that such condition bore a “nexus” to the crime. Id. at 2569-70, 2573. The Supreme Court has subsequently characterized the “nexus” requirement as “a test we never countenanced and now have unequivocally rejected.” Smith v. Texas, — U.S. —-, —-, 125 S.Ct. 400, 405, 160 L.Ed.2d 303 (2004).
Here, the prosecutor gave the jury two reasons to believe Sims’s background did not constitute legally cognizable mitigating evidence. First, according to the prosecutor, having a bad background is too common among criminal defendants to act as a mitigating factor: “If that were, therefore, *598a mitigating factor, then you would be emptying prisons because it would apply to vertually [sic] everybody.... Were it a mitigating factor that a person had a bad childhood, then you would have no death penalty statute at all.” Second, in the prosecutor’s view Sims’s mitigating evidence was disqualified as a factor to be considered and weighed by the jury because of the absence of a connection between Sims’s background and his crime: “There is no bridge that bridges this bad background to anything we have in the case before us.... What happened to Mr. Sims, as bad as it was, was ten years before the crimes in question.... What does it mean in terms of assigning a mitigating factor to it? What does it mean in terms of punishment? It doesn’t mean a thing. There is no mitigating factor there ” (emphasis added). Under the Supreme Court’s Eighth Amendment jurisprudence, the prosecutor’s argument was wrong on both counts.
When the Supreme Court “addressed directly the relevance standard applicable to mitigating evidence in capital cases,” it “spoke in the most expansive terms.” Tennard, 124 S.Ct. at 2570 (describing McKoy). Discounting an aspect of a defendant’s background because he shares it in common with other defendants is the antithesis of the individualized consideration the Supreme Court has found indispensable to a capital sentencing process that comports with the Eighth Amendment. See, e.g., Eddings, 455 U.S. at 112, 102 S.Ct. 869. Thus, the Supreme Court has rejected the proposition that mitigating evidence can be restricted to facts about the defendant that are “uniquely severe.” Tennard, 124 S.Ct. at 2569-70. The prosecutor’s “bridge” theory is equally faulty: the requirement that mitigating evidence bear some connection to the defendant’s crime is one that the Supreme Court “never countenanced and now [has] unequivocally rejected.” Smith, 125 S.Ct. at 405 (citing Tennard). Thus, it is clear that the prosecutor misstated the law of mitigating evidence in both of the respects Sims alleges.
The prosecutor’s misstatements of law entitle Sims to reversal of his death sentence if “there is a reasonable likelihood that the jury has applied the challenged instruction in a way that prevents the consideration of constitutionally relevant evidence.” Boyde, 494 U.S. at 380, 110 S.Ct. 1190. Though “arguments of counsel generally carry less weight with a jury than do instructions from the court,” the Supreme Court has acknowledged that prose-cutorial misstatements of law may “have a decisive effect on the jury.” Id. at 384, 110 S.Ct. 1190. “[T]he arguments of counsel, like the instructions of the court, must be judged in the context in which they are made.” Id. at 385, 110 S.Ct. 1190.
Viewed in context, the prosecutor’s statements during Sims’s penalty phase more than likely misled the jury and clearly were intended by the prosecutor to persuade the jury that they could not consider Sims’s dreadful childhood. The prosecutor did not merely argue (as the majority would have it) that Sims’s mitigating evidence lacked persuasive power; rather, the prosecutor repeatedly argued both implicitly and explicitly that Sims’s background was not legally cognizable mitigating evidence at all. By hypothesizing what would happen “[i]f in fact, it were a mitigating factor that a person had a bad childhood” (emphasis added), the prosecutor clearly implied that a bad childhood is, in fact, not a mitigating factor. I agree with the California Supreme Court’s conclusion in Sims’s direct appeal that “the prosecutor’s comment that the troubled background of a defendant does not constitute a mitigating factor might have tended to suggest erroneously that the jury could *599not consider such evidence in mitigation.” Sims, 20 Cal.Rptr.2d 537, 853 P.2d at 1029. If anything, this is an understatement. The prosecutor was even more explicit in his assertion that the absence of a connection between Sims’s background and his crime disqualified his background as mitigating evidence: “There is no bridge that bridges this bad background to anything we have in the case before us.... It doesn’t mean a thing. There is no mitigating factor there ” (emphasis added).7
The prosecutor’s clear message — that Sims’s background was not mitigating evidence for two reasons — was not confined to an isolated or offhand remark. On the contrary, the prosecutor made extensive use of both of his theories as to why Sims’s background categorically did not qualify as mitigating evidence. Three times the prosecutor invoked the prevalence of troubled backgrounds among the criminal population to suggest that a bad background is not mitigating evidence. The prosecutor’s invocation of the “bridge” theory was even more ubiquitous: in total, the prosecutor used the word “bridge” or some form of the word “connection” in reference to Sims’s background no fewer than seventeen times during the penalty phase closing. Perhaps most damaging, on three occasions the prosecutor told the jury flat out that Sims’s background was “not a mitigating factor,” that “[tjhere is no reason for mitigating factors,” that “[tjhere is no mitigating factor there.” Although determining the effect of the prosecutor’s closing on the jury is not a mere matter of counting words or phrases, in this case the numbers are a reasonable barometer of the extent to which the prosecutor’s misstatements of the law were a point of emphasis with the jury.
Squarely on point is our en banc decision in Payton v. Woodford, 299 F.3d 815 (9th Cir.2002) (en banc) (“Payton I”), vac’d on other grounds, 538 U.S. 975, 123 S.Ct. 1785, 155 L.Ed.2d 662 (2003), on remand at Payton v. Woodford, 346 F.3d 1204 (9th Cir.2003) (en banc) (“Payton II”), rev’d sub nom. Brown v. Payton, — U.S.-, 125 S.Ct. 1432, 161 L.Ed.2d 334 (2005) (“Payton III ”).8 In Payton I, we affirmed the grant of a habeas petition as to a death sentence because an ambiguous instruction (a forerunner of the factor (k) instruction given at Sims’s trial), combined with prosecutorial misstatements of the law, had prevented the jury from considering mitigating evidence of the defendant’s post-crime religious conversion. 299 F.3d at 820-23, 830. While Sims does not argue (as Payton did) that the factor (k) instruction itself was inherently ambiguous, “[tjhe prosecutor’s arguments can*600not be isolated from the instruction itself or from the failure of the trial judge properly to instruct the jury or to correct the prosecutor’s error.” Id. at 823. The prosecutorial misrepresentations of law that occurred in Sims’s case bear a striking resemblance to those we refused to countenance when we applied pre-AEDPA habeas standards in Payton I.
There as here, the prosecutor asserted several times (erroneously) that factor (k) did not permit jurors to consider in mitigation precisely the type of evidence that the defendant had offered. Id. at 821. There as here, the prosecutor told the jury that they had “not heard any evidence of mitigation in this trial.” Id. If anything, the misstatements of the law in Sims’s case were more injurious than those in Payton’s because Sims’s prosecutor offered the jury two erroneous legal principles as alternative bases for disregarding Sims’s mitigating evidence. And there as here, the prosecutor did not merely “argue[ ] that in his view the evidence did not sufficiently mitigate [the defendant’s] conduct,” Boyde, 494 U.S. at 385, 110 S.Ct. 1190 (citation and internal quotation marks omitted); rather, “the prosecutor here told the jurors that the statutory list of factors “precluded them from considering the only mitigating evidence [the defendant] presented.” Payton I, 299 F.3d at 825 (emphasis altered).9 The majority’s contrary conclusion is belied by the record of what Sims’s prosecutor actually said, which can be summed up in six of his own words: “[t]here is no mitigating factor there.”
In sum, the prosecutor misstated the law repeatedly and extensively. His erroneous “bridge” theory was a particular point of emphasis. The prosecutor’s eon-elusion that “[t]here is no mitigating factor there,” which he reiterated to the jury on several occasions, explicitly instructed the jury to disregard' — not just to devalue— the mitigating evidence that Sims offered. The trial court failed to give any sort of curative instruction directed at the prosecutor’s misstatements of the law; what instructions the court did give were entirely inadequate. Coupled with the court’s refusal to correct the prosecutor when there was objection, this left the jury with the uncorrected and inaccurate impression that Sims’s background did not qualify as mitigating evidence, because he had not established a “bridge” between his background and his crime, and because a troubled background is too common among criminals to count as a mitigating factor. Consequently, there is at least “a reasonable likelihood that the jury has applied the challenged instruction in a way that prevents the consideration of constitutionally relevant evidence.” Boyde, 494 U.S. at 380, 110 S.Ct. 1190.
IV. Injurious Effect of the Prosecutor’s Misstatements
I circle back to the issue with which I began: whether the error meets the Brecht standard for harmfulness. The Supreme Court has explained that the Boyde test “is not a substitute for the Brecht harmless-error test. The Boyde analysis does not inquire into the actual effect of the error on the jury’s verdict; it merely asks whether constitutional error has occurred.” Calderon v. Coleman, 525 U.S. 141, 146-47, 119 S.Ct. 500, 142 L.Ed.2d 521 (1998) (per curiam).
Here, there is at least “grave doubt” as to whether the constitutional error *601wrought by the prosecutor’s repeated mis-charaeterizations of the law of mitigation had a “substantial and injurious effect or influence” on the verdict. O’Neal, 513 U.S. at 436, 115 S.Ct. 992 (internal quotation marks omitted). The crime was unquestionably brutal. The evidence against Sims was strong. Several aggravating factors were present, including Sims’s commission of two other murders, and the horrific circumstances of this one. The callous nature of Sims’s conduct and his leading role in the murder also weigh against him.
But Sims’s childhood abuse was quite shocking as well, as even the prosecutor admitted. The prolonged and continuous physical, emotional, and sexual abuse he endured at the hands of his stepfather may well have been sufficient to generate enough sympathy to move a jury to spare Sims’s life — had the jury understood that it was its duty to consider it. Instead, there is at least a “reasonable likelihood that,” as a result of the prosecutor’s repeated distortions of the law as to the role of mitigating evidence, “the jury has applied the challenged instruction in a way that prevented] the consideration of constitutionally relevant evidence.” Boyde, 494 U.S. at 380, 110 S.Ct. 1190. Because Sims’s troubled background was central to his mitigation defense, the prosecutor’s insistent assertion that the jury could not consider Sims’s background “left the jury bereft of any countervailing evidence to weigh against the prosecution’s evidence of aggravating circumstances.” Payton I, 299 F.3d at 829. It is difficult to imagine that the jury’s calculus would not have changed significantly had the powerful evidence of Sims’s background been brought to bear.
The defendant “for whom life or death hangs in the balance deserves the benefit of the doubt.”. Mayfield v. Woodford, 270 F.3d 915, 933 (9th Cir.2001) (en banc) (Gould, J., concurring) (internal punctuation omitted). In Sims’s case, ultimately “[w]e cannot know whether the jury would have returned a verdict of life or of death had it been properly instructed.” Payton I, 299 F.3d at 829. Given “grave doubt” as to the harmlessness of the error, reversal is the prescribed course. O’Neal, 513 U.S. at 436, 115 S.Ct. 992. I would hold that the prosecution’s misstatements of the law of mitigating evidence violated the Eighth Amendment and that Sims is entitled to relief from his death sentence.
Y. Cumulative Error
“Even if no single error were sufficiently prejudicial, where there are several substantial errors, their cumulative effect may nevertheless be so prejudicial as to require reversal.”
Alcala v. Woodford, 334 F.3d 862, 893 (9th Cir.2003) (citations, internal quotation marks, and source’s brackets omitted). Even were the Miranda and Eighth Amendment violations insufficient on their own to warrant habeas relief from the penalty-phase verdict, the combined effect of these errors certainly prejudiced Sims and warrants setting aside the death sentence.
In this case, the Miranda and Eighth Amendment violations present a particularly compelling claim of cumulative error, because the combined effect of these errors was more powerful than that of the errors taken individually. The prosecutor’s emphasis on Sims’s statements “I had to kill that boy” and “I knew I was doing it, but I shouldn’t [have] done it,” and the prosecutor’s repeated insistence to the jury that Sims’s background was not mitigating evidence, comprised two of the major themes of the prosecutor’s penalty-phase closing argument. Cf. Alcala, 334 F.3d at 893 (finding cumulative error in *602part because “the cumulative impact of the eri-ors goes to the heart of the prosecution’s theory of the case”). As I have noted, the prosecutor’s closing argument emphasized both Sims’s lack of remorse (as demonstrated in the December 25 and 26 conversations with Officer Perkins) and Sims’s supposed failure to present mitigating evidence. Additionally, the tape of Sims’s December 26 statements — which included the admission “I knew I was doing it, but I shouldn’t[have] done it” — was replayed for the jury during the prosecution’s penalty phase case.
Just as significant as the extent of the constitutionally impermissible comments was their force. The prosecutor’s reiteration of the statements “I had to kill that boy” and “I knew I was doing it, but I shouldn’t [have] done it” — both obtained in violation of Miranda — focused the jury’s attention on what was probably the most powerful evidence of Sims’s guilt. They completely foreclosed any attempt to argue lingering doubt as to intent. They formed the backbone of the prosecutor’s argument that Sims’s lacked remorse. Equally damaging, the prosecutor’s misrepresentations of the law of mitigation invited the jury to disregard evidence of Sims’s awful childhood, which was substantially the only evidence Sims offered in mitigation.
These errors — if not separately, then certainly together — undermined the fairness of the process by which Mitchell Sims was sentenced to death: in one morning, in one concentrated pitch to the jury just hours before they retired to deliberate, the prosecutor stressed powerful but constitutionally inadmissible evidence in support of death and improperly undercut practically all of Mitchell Sims’s evidence in favor of life. As a result of these errors, the jurors quite likely commenced their deliberations with the wrong mind-set.
“The collective presence of these errors is devastating to one’s confidence in the reliability of this verdict[.]” Killian v. Poole, 282 F.3d 1204, 1211 (9th Cir.2002). Faced with two substantial penalty-phase errors and their correspondingly serious effects on the evidence Mitchell Sims’s jury considered in imposing its sentence of death, we should follow the Supreme Court’s example and refuse to “risk that the death penalty will be imposed in spite of factors which may call for a less severe penalty. When the choice is between life and death, that risk is unacceptable and incompatible with the commands of the Eighth and Fourteenth Amendments.” Penny, 492 U.S. at 328, 109 S.Ct. 2934 (citations and internal quotation marks omitted).
I respectfully dissent from the majority’s decision to uphold Sims’s death sentence.
. It held:
We conclude defendant's statement that he 'had to kill that boy,' his repetition of that statement, and his third statement that the victim would have identified him, were elicited in contravention of Miranda. All three statements should have been excluded from evidence. The trial court’s denial of defendant’s motion to suppress these statements therefore constituted error. The three statements constituted a confession, i.e., a declaration of defendant's intentional participation in the murder. (See People v. McClary, [] 20 Cal.3d 218, 142 Cal.Rptr. 163, 571 P.2d 620 (1977)).
853 P.2d at 1015.
. Because "the availability of the Fifth Amendment privilege does not turn upon the type of proceeding in which its protection is invoked, but upon the nature of the statement or admission and the exposure which it invites,” the Supreme Court has found "no basis to distinguish between the guilt and penalty phases of [a] capital murder trial so far as the protection of the Fifth Amendment privilege is concerned.” Estelle v. Smith, 451 U.S. 454, 462-63, 101 S.Ct. 1866, 68 L.Ed.2d 359 (1981) (citation, internal quotation marks, source’s alteration marks, and footnote omitted). Therefore, Miranda’s exclusionary rule regarding improperly obtained unfavorable statements applies with equal force to both the penalty and guilt phases. Id. ("Just as the Fifth Amendment prevents a criminal defendant from being made 'the deluded instrument of his own conviction,' [], it protects him as well from being made the 'deluded instrument' of his own execution.” (internal quotation marks and citations omitted)); cf. Jones v. Cardwell, 686 F.2d 754, 756 (9th Cir.1982) (holding that the Fifth Amendment protects defendant against self-incrimination in non-capital case for purposes of increasing sentence based on judicial fact-finding).
. The district court's determination that Sims inquired about "why Perkins was there, and his authority for being there” is unsupported by the record. Indeed, the pages cited by the district court demonstrate that Perkins understood Sims’s questions to be related to "purely extradition.” Despite this understanding, Perkins continued to speak of subjects far afield from extradition. The district court’s factual finding in this regard is clearly erroneous.
. Sims's explanation that "he was going to identify me” was heard by the jury twice more during cross examination and once more during re-direct.
. The details are so gruesome that I do not belabor them here. If the reader needs to refresh his or her memory, turn to the majority opinion, at 566-67.
. The record offers scant support for the majority's conclusion that the confusion sown by the prosecutor's improper arguments was in any way dispelled by the court's instructions or the arguments of defense counsel. The court's instructions on mitigating evidence were of the most general nature, were far removed in time from the prosecutor's misstatements of the law, and were not addressed to counteract these misstatements. When the prosecutor presented his erroneous theories, no curative instruction was given. Even worse, when defense counsel objected, the court overruled him, thereby implicitly placing the court's own imprimatur on the prosecutor's improper argument.
Nor could the jury’s confusion have been ameliorated by the arguments of defense counsel, who at first suggested that no bridge was required and later argued as if it were. Moreover, it is doubtful whether the arguments of defense counsel alone could ever suffice to cure misleading arguments by the prosecutor, as the jury is likely to view a debate between defense and prosecution as *596merely inviting resolution of the issue by the jury. Such a result does not cure the constitutional violation. See Payton v. Woodford, 299 F.3d 815, 825-26 (9th Cir.2002) (en banc) ("In effect, the court’s instruction delegated to the jury the legal question whether factor (k) allowed consideration of Payton’s mitigating evidence. Nothing prevented the jury from refusing to consider Payton’s mitigating evidence and thereby reaching an unconstitutional result.”), vac’d on other grounds, 538 U.S. 975, 123 S.Ct. 1785, 155 L.Ed.2d 662 (2003), on remand at Payton v. Woodford, 346 F.3d 1204 (9th Cir.2003) (en banc), rev'd sub nom. Brown v. Payton, - U.S. -, 125 S.Ct. 1432, 161 L.Ed.2d 334 (2005).
. The prosecutor’s closing was replete with implicit as well as explicit assertions that a connection between Sims’s background and his crime was a prerequisite to the jury's consideration of that background as mitigating evidence. For example:
So, again, we are searching for a bridge, we are searching for some kind of bridge. I suppose if the offense was against his stepfather, certainly it would be relevant, then, wouldn’t it? No question about that,
(emphasis added). Again, by posing a hypothetical in which Sims's background “would be relevant,” the prosecutor clearly implied that it was not relevant in Sims’s case.
. Payton I granted relief under pre-AEDPA law, see 299 F.3d at 822, 830, and the Supreme Court summarily vacated and remanded for reconsideration of whether AEDPA applied to Payton’s petition. See 538 U.S. 975, 123 S.Ct. 1785, 155 L.Ed.2d 662 (citing Woodford v. Garceau, 538 U.S. 202, 123 S.Ct. 1398, 155 L.Ed.2d 363 (2003)). In so doing, the Court suggested only that we had applied the wrong standard of review, not that our application of that standard was faulty. Pay-ton I remains good law with respect to the determination of a claim — such as Sims’s — of Eighth Amendment instructional error evaluated under pre-AEDPA standards.
. I note that Sims’s family witnesses also testified to Sims's generosity and that his children worshiped him and urged that his life was worth saving; however, this testimony was brief and limited. Aside from these few remarks, Sims's case in mitigation consisted entirely of the compelling evidence of his traumatic childhood.